The invention concerns a device in concrete blocks which are intended to be interconnected in end-to-end positions to delimit roadways, parking lots and similar enclosed areas, and which concrete blocks are intended to guide vehicles that leave the roadway back to their normal driving path while ensuring that any damage that might be caused to the vehicle is as slight as possible and also that the vehicle is not guided over to the side of the roadway of oncoming traffic.
Devices used to interconnect concrete blocks of the kind referred to must be such as to allow the blocks, when they are placed in position, to be easily interconnected and also, when needed, be easily disconnected, as this saves labour and therefore considerable costs.